1. Field of the Invention
The present invention relates generally to shoe inserts and, more specifically, to disposable cushion inserts for shoes designed to temper forces imparted on a foot during activities such as walking and running.
The cushion insert in one embodiment has a cover layer and an open-cell shape-retentive layer conjoined by means of a bonding method taken from the group of adhesive and ultrasonics.
The cover layer is constructed of fibrous material taken from the group of fiber crops and polymers that will be treated to have a low moisture content and absorbency with a plurality of apertures passing therethrough as air passages between the open-cell layer and the cushioned insert exterior.
The second layer is manufactured from a cross-linked open cell silicone material having a plurality of conjoined truncated-apex square pyramids where the walls enclose a central cavity with open bottoms providing a structure that is mostly ambient air-filled space that when released from a compressed state returns to its original form. Each of the pyramids' truncated-apex top surfaces has an aperture placed therethrough providing passage for air between each of the pyramid-shaped cavities and the cushioned-insert exterior.
The aforementioned bonding of the cover and open-cell layers takes place between the top planar surfaces of the apex-truncated pyramids and the surface area of the first layer engaging the apex-truncated pyramids.
As aforementioned, both the cover and open-cell layers have a plurality of apertures with the pyramid apex apertures co-aligning with the cover layer apertures. Additional apertures are placed in the cover layer in fluid communication with the spaces between the second layer's spaced apart pyramids providing for additional venting of air from the open-cell layer through the cover to the cushioned insert exterior.
The present invention also provides for an embodiment having a base layer conjoined to the base of the open-cell layer manufactured from a frictional material to prevent slippage of the cushioned insert during use.
2. Description of the Prior Art
There are other shoe inserts designed for similar purposes. While these shoe inserts may be suitable for the purposes for which they were designed, they would not be as suitable for the purposes of the present invention, as hereinafter described.
U.S. Pat. No. 231,398 of Bussey discloses air cavities covered by an insole with smaller holes but does not teach a collapsible structure with superadjacent apertures for channeling air across the foot.
U.S. Pat. No. 682,141 of Galloway teaches a shoe cushion insert with exterior venting air pockets with channels between the air pockets for venting. This design would result in a lumpy insert due to the varying cross sectional thicknesses of the insert.
U.S. Pat. No. 825,515 of Byrne discloses a dual layer insert having a plurality of imperforate frusto conical air pockets that would entrap air as a cushioning member while venting the air below along the periphery. It does not teach an insert that would unilaterally collapse expelling all air contained therein.
U.S. Pat. No. 1,128,220 of Bullard discloses an insert comprised of independent cells that vent out the bottom of the insert. It is believed that sufficient pressure would keep the cells from venting at all. Furthermore, such a design would be limited to a heel cushion as shown since a full shoe insert would cause pressure and soreness across the instep due to the contour of the foot.
U.S. Pat. No. 1,605,408 of Huiskamp teaches a permanent air cushion positioned between the inner and outer sole with a plurality of protuberances and a single ingress and egress port positioned in the insole. Such a design would have limited capability of moving air across the body of the foot.
U.S. Pat. No. 2,090,881 of Wilson teaches a bubble-wrap type insert with sealed air pockets which does not provide for the exchange of air within the insert due to changes in pressure.
U.S. Pat. Nos. 2,347,207 and 2,432,533 of Margolin teaches an insole with a plurality of hexagonal shaped pockets with exterior opening for moving air in and out of the insert. The insert does not disclose a disposable insert having a wall structure creating an interior ventable compartment and an exterior ventable compartment.
U.S. Pat. No. 3,231,454 of Williams teaches a cushioning material with a plurality of spaced columnar-shaped projections. The cushioning material does not disclose a wall structure creating an interior ventable compartment and an exterior ventable compartment.
U.S. Pat. No. 3,589,037 of Gallagher teaches a plurality of air pockets formed from heat sealing two sheets together, which does not provide for air movement from the insert during activity.
U.S. Pat. No. 3,616,155 of Chavannes also teaches an insert comprised of a plurality of sealed air pocket, which does not provide for air movement.
U.S. Pat. No. 6,434,859 of Kim teaches a plurality of protrusions with a topmost aperture and a base skirt which under pressure collapses causing the egress of air from the base positioned cavity. This construction does not disclose a wall structure creating an interior ventable compartment and an exterior ventable compartment.